An explosive new report from the U.S. Department of Energy makes clear that Liquefied Natural Gas (LNG) is likely a climate-destroying misallocation of resources.
That is, if one uses estimates for methane leakage based on actual observations.
This is the same conclusion I reached back in 2012, based on
- Emerging analyses of how even a relatively low leakage rate in the natural gas production and delivery system negate its climate benefit, and
- A 2009 EU report on how the energy-intensive liquefaction process and transportation further increase LNG emissions.
Again, natural gas is mostly methane, and some 86 times (to as much as 105 times) better at trapping heat than carbon dioxide.
One of the country’s leading experts on natural gas leaks told me, “a close reading of the DOE report in the context of the recent literature indicates that exporting natural gas from the U.S. as LNG is a very poor idea.”
So you may wonder why the Financial Times had this headline on its story: “US LNG exports could help countries curb emissions.”
To make LNG a climate winner, you’d have to assume levels of methane leakage that are a factor of 2 to 3 lower than what recent observations reveal. That is exactly what DOE’s National Energy Technology Laboratory (NETL) does in its analysis, “Life Cycle Greenhouse Gas Perspective on Exporting Liquefied Natural Gas from the United States.”
Here is the stunning (if confusing) chart from the DOE report:
FIGURE 6-9 depicts the life cycle GHG emissions for the U.S. LNG and Russian natural gas scenarios as a function of the methane leakage that occurs during extraction, processing, and transport on a 20-year basis. It also includes a reference line for the coal power scenario. The diamond-shaped data points represent the modeled leakage for each scenario and the circular data points represent the breakeven leakage at which the life cycle GHG emissions for natural gas power would equal those for the coal reference case.
Yes, despite multiple studies to the contrary, the DOE is asserting that the leakage rate is very low in the U.S. (but not in Russia, of course) — so low that U.S. LNG just happens to be better for Europe than its own coal:
“The high modeled leakage rate for the U.S. LNG scenarios (1.6 percent) is still less than the breakeven percentage for the European scenario (1.9 percent), but slightly higher than the breakeven for the Asian scenario (1.4 percent)…. As previously noted, the calculated breakeven points are the most conservative, so these results do not indicate that natural gas has a higher GHG than coal on a 20-year basis in all cases.”
The DOE is actually asserting that the absurdly low leakage rate of 1.6 percent is conservative! How conservative? Look at this table:
For DOE, 1.6 percent leakage is the highest leakage rate they considered!! And 1.4% is what they expect for shale gas. #FAIL
In fact, leakage rates are almost certainly at least double that! Yes, the EPA has lowered its estimate to about 1.5 percent — based solely on industry-provided numbers. But multiple studies in the last two years based on actual observations have made clear the EPA was simply wrong.
Back in November, fifteen scientists from some of the leading institutions in the world — including Harvard, NOAA and Lawrence Berkeley National Lab — published a seminal observation-based study, “Anthropogenic emissions of methane in the United States.” The authors took the unusual step of explicitly criticizing the EPA: “The US EPA recently decreased its CH4 emission factors for fossil fuel extraction and processing by 25–30% (for 1990–2011), but we find that CH4 data from across North America instead indicate the need for a larger adjustment of the opposite sign.”
How much larger? The study found greenhouse gas emissions from “fossil fuel extraction and processing (i.e., oil and/or natural gas) are likely a factor of two or greater than cited in existing studies.” In particular, they concluded, “regional methane emissions due to fossil fuel extraction and processing could be 4.9 ± 2.6 times larger than in EDGAR, the most comprehensive global methane inventory.”
This suggests the methane leakage rate from natural gas production is in fact 3 percent or higher.
A comprehensive Stanford study from February suggested things might even be worse: “A review of more than 200 earlier studies confirms that U.S. emissions of methane are considerably higher than official estimates. Leaks from the nation’s natural gas system are an important part of the problem.” Their analysis finds:
“… an excess percentage leakage of 1.8% to 5.4% of end use gas. Coupled with the current estimate of 1.8% leakage of end use gas consumed, this generates a high-end estimate of 7.1% gas leakage.”
Ouch.
After discussing the matter with the lead author, Stanford’s Adam Brandt, I wrote that given the risks to humanity from climate change, it seems conservative to take the middle of the range, 5.4%. That’s particularly conservative given that 3 separate studies by NOAA found leakage rates just from NG production of 4%, 17%, and 6-12%!
[In case you wondered if the Stanford study was too recent for NETL to include in its May 29 report, NETL released another report on natural gas emissions the same day that cites it several times.]
If one were to use 3 percent as the leakage rate, LNG-fueled power plants would be worse than coal from a climate perspective for decades. If you use 5.4 percent, then Figure 6.8 makes clear LNG-fueled power plants are worse than coal for a century!
Finally, the recent observation-based calculations of methane leakage are quite similar to that estimated in the much-maligned (but apparently correct) 2012 Cornell study led by Cornell’s Bob Howarth. So I asked Howarth for comment on NETL’s report. He replied:
The NETL report seems determined to prove that LNG export from the US is desirable from a climate perspective, and the authors have torqued their analysis in several ways to reach this conclusion. A big omission is their failure to consider methane emissions from the LNG tankers and storage tanks: “boil off,” or the purposeful release of LNG that provides evaporative cooling to maintain the liquid status of the LNG. LNG tankers try to capture most of this boil off, but even small losses are highly significant and can make LNG a disastrous fuel from the standpoint of global warming. I find it remarkable that the NETL report does not even mention methane emissions from boil off.
Despite these shortcomings, a close reading of the NETL report in the context of the recent literature indicates that exporting natural gas from the US as LNG is a very poor idea. For instance, their figure 6.9 shows that coal has a lower greenhouse gas footprint than exported LNG if the upstream methane emission rates are greater than 1.6% to 1.9%, when considered over an integrated 20-year time period following the methane emission, even when though they are ignoring the boil-off emissions. Because of risk of hitting tipping points in the climate system due to climatic warming from methane emissions over the cover few decades, this shorter time frame of analysis is critical. And current upstream methane emissions from shale and other unconventional natural gas are almost certainly greater than these break-even values of 1.6% to 1.9%, as shown by much recent literature summarized in my paper published last month (online here).
Precisely.
One final point: Contrary to the implication of NETL’s analysis, natural gas doesn’t just displace coal — it also displaces carbon-free sources of power such as renewable energy, nuclear power, and energy efficiency. A recent analysis finds that effect has been large enough recently to wipe out almost the entire climate benefit from increasing natural gas use in the U.S. utility sector if the leakage rate is only 1.2 percent.
BOTTOM LINE: Investing billions of dollars in new shale gas infrastructure for domestic use is, as we’ve seen, a bridge to nowhere — especially until we put in place both a CO2 price and regulations to minimize methane leakage. The extra emissions from LNG completely eliminate whatever benefit there might be of building billion-dollar export terminals and other LNG infrastructure, which in any case will last many decades, long after we need a nearly carbon-free electric grid. At best, investing billions in LNG infrastructure is a waste of enormous resources better utilized for deploying truly low-carbon energy. At worst, it helps accelerate the world past the 2°C (3.6°F) warming threshold into Terra incognita — a planet of amplifying feedbacks and multiple simultaneous catastrophic impacts.
*If one uses estimates for methane leakage based on actual observations.
Courtesy of Thinkprogress
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